Under the latest forecast, Rina would approach or hit Mexico’s Yucatan Wednesday night or Thursday as a major hurricane and make a hard turn northeast on Friday.

It would downgrade to a tropical storm as it approaches the west end of Cuba and aim almost due east. If that prediction holds, the core would remain south of the Keys.

However, long-range forecasts can contain large errors and some models predict the system will move over the Keys or South Florida on Sunday or Monday, likely as a tropical storm.

"If Rina moves farther inland over the Yucatan Peninsula than expected, it could be weaker than forecast in two or three days," hurricane specialist Mike Brennan wrote in the lastest advisory.

Whether Rina remains south of the state or not, the system is expected to increase South Florida’s rain chances starting on Wednesday night and Thursday, said meteorologist Brad Diehl of the National Weather Service in Miami.

The hurricane center also is monitoring an area of low pressure in the southeast Caribbean, giving it a 10 percent chance of developing. The system was moving west at 15 mph. Models aim it generally toward the Gulf of Mexico.